1. Field of the Invention
This invention relates to an improved plaque removal device for teeth consisting of a toothbrush which vibrates and generates in the brush portion an ultrasonic wave to assist in loosening plaque.
2. Description of the Prior Art
The present invention combines the capability of ultrasonic or high frequency sound waves to clean objects including teeth, with vibratory motion similar to that of an electric toothbrush, to produce an improved device for removing plaque from teeth.
Ultrasonic sound wave vibrations above 20 KHz are generally produced by a transducer containing a piezoelectric or similar substance such as a quartz crystal oscillator which converts high frequency electric current to into vibrating ultrasonic waves. Ultrasound has found wide industrial use, particularly in the nondestructive testing of manufactured objects and the cleaning of many objects. Cleaning is often accomplished by immersing the object into a cleaning liquid into which ultrasonic waves are propagated, with the cavitating liquid removing film or dirt even from inaccessible regions. In medicine, ultrasound has been used to examine organs without surgery, and has been found to be far safer than x-rays.
Ultrasonics has also been applied to the cleaning of teeth. The removal of plaque is important to good dental health. Plaque is a thin, colorless, sticky film that constantly forms on the teeth. When foods containing sugars and starches are eaten, the bacteria in plaque produces acids which attack tooth enamel. The stickiness of the plaque keeps these acids in contact with teeth. After many such attacks, the enamel breaks down and a cavity forms.
If plaque is not removed by daily brushing, flossing or other techniques, it hardens into calculus (tartar). As calculus forms near the gumline, gums can become irritated and inflamed. They become swollen and may bleed. The gums begin to pull away from the teeth and form pockets that may become infected. If this gum disease is not treated promptly, the bone supporting the teeth is destroyed and healthy teeth may be lost.
Many prior art devices use ultrasound to remove plaque from teeth. In U.S. Pat. No. 5,013,241 to vonGutfeld et al., a dental tool is shown for cleaning plaque from teeth by focusing an ultrasound wave into a jet of liquid such as water which is then directed as a stream upon the teeth.
Other devices use ultrasonic energy in periodontics. Commercially available units incorporate a solid metal tip to which appropriate ultrasonic energy is applied. The vibrating metal tip is used to contact the surface of a tooth in order to remove plaque therefrom. Because of heat buildup, cooling and rinsing water flows are normally used in association with the metal tip. Such devices can be uncomfortable due to the high intensity vibrations produced, which can cause nerve pain. High pitched audible sounds are generated and can be uncomfortable. Devices of this type are primarily dentist's tools and cannot be used at home.
Other prior art devices utilizing ultrasonics are U.S. Pat. No. 4,920,954 to Alliger et al. in which a solid titanium wire is inserted into the artery of a human, and ultrasound vibrations are applied to the wire to produce a cavitation force for the removal of plaque from the artery. U.S. Pat. No. 4,944,296 to Suyama incorporates a piezoelectric element into the handle of a toothbrush, the bending of the handle which occurs during normal tooth brushing causing the generation of electrons which remove that dental plaque which is charged with positive electricity.
The present invention provides a unique plaque removal device consisting of a toothbrush having an electric motor in the handle thereof causing rotation of an eccentric member which produces rotational vibration of the entire toothbrush. Also in the handle is an ultrasonic transducer which produces ultrasonic waves that are coupled into the brush portion of the toothbrush and are propagated from the brush portion non-directionally in the mouth. The combination of the rotational vibration of the brush and the production of the standing ultrasonic waves provides improved tooth cleaning capability.
Because the device of this invention does not suffer from the disadvantages of the ultrasonically vibrating metal tip devices, it can safely be used a home as part of a person's every day routine of tooth brushing. It provides considerable advantages over brushing with a standard or even an electric toothbrush because the vibrations of the brush combined with the generation of the ultrasonic waves loosens the plaque in places that are normally not reached by standard toothbrushes. This results in considerably cleaner, plaque free teeth and prevents gum disease and bone loss. The vibrations of the brush will more easily remove plaque from teeth where the plaque has previously been loosened by the ultrasonic waves. The ultrasonic waves are not focused and are general to the entire region about the brush in which the standing wave is produced. The waves will be more apparent at the end of the brush which vibrates more freely, particularly if the ultrasonic wave length is advantageously selected to correspond to the length of the brush portion. The combined action of the rotational vibration and the ultrasonic waves will be far more effective than brushing alone, or brushing combined with flossing, in loosening and removing plaque from teeth.
It is therefore an object of this invention to produce a unique plaque removal device which comprises a vibrating toothbrush in combination with the generation and propagation of ultrasonic waves along the brush portion of the toothbrush.
Another object of this invention is a toothbrush that vibrates in a rotational manner, and which contains an ultrasonic transducer generating high frequency sound waves in the toothbrush in order to loosen plaque.
A further object of this invention is a toothbrush having a battery driven motor causing rotation of an eccentric member producing rotational vibration of the entire toothbrush, and an ultrasonic transducer coupled to the toothbrush which generates ultrasonic waves therein.
A still further object of this invention is a vibrating toothbrush in which an ultrasonic transducer generates high frequency sound waves to loosen plaque on the teeth.